Fulminant hepatic failure (FHF) is a syndrome defined as necrosis of a large number of liver cells or severe impairment of liver function and hepatic encephalopathy within 8 weeks after the initial symptom or within 10 days of the on-set of jaundice in the absence of previous liver disease. It is characterized by rapid on-set, severe condition, absence of effective treatment and high mortality.
The acute inflammation and necrosis of liver cells may lead to two different diseases: acute hepatitis and fulminant hepatic failure (also called acute hepatic failure). Acute hepatitis caused by hepatitis virus is referred to as acute viral hepatitis, and the acute hepatitis caused by alcohol is called as acute alcoholic hepatitis. Although necrosis of liver cells is widely seen in all kinds of hepatitis described above, the necrosis is not so severe to lead to hepatic dysfunction. FHF is distinguished from various acute hepatitis in that awfully rapid necrosis of liver cells happens in FHF, resulting in hepatic failure due to dysfunction of the remaining normal hepatocytes, and eventually leading to extremely high mortality.
The leading cause of FHF in China is hepatitis virus infection, while other causes including medical or poison toxicosis, ischemia and anoxia, metabolic disorder, and autoimmune hepatitis, etc. Currently no medicaments are available to specifically block the acute necrosis of liver cells, and thus hepatic failure due to large quantities of hepatic cell necrosis cannot be prevented. As a result, it keeps ongoing difficult to reduce the mortality of FHF, and there is an urgent clinical need for a medicament capable of specifically and rapidly preventing acute hepatic cell necrosis, thereby treating hepatic failure.
Recent studies have revealed that binding of TNFα and its receptor is the first pathway to trigger hepatic cell necrosis, which plays an important role in the mechanism of hepatocyte impairment. Blocking said binding will block the starting point of hepatic cell necrosis, whereby enabling the pharmaceutical treatment of FHF.
At present, there are two classes of TNFαinhibitor that directly interrupt the binding of TNFαand its receptor: monoclonal antibody against TNFα, and soluble TNFα receptor analogue. These TNFαinhibitors, which bind TNFαin vivo, will theoretically prevent the binding of TNFα in blood or intercellular fluid to its receptor on the membrane of hepatocytes, thereby preventing the activation of the cell necrosis pathway.
Recent studies found that monoclonal antibody of TNFα is not a suitable candidate medicament due to its characteristic of activating TNFα on cell membrane which leads to apoptosis of the target cells, in addition to its ability to block the binding of TNFαto TNFα receptor type I.
The conventional soluble TNFαreceptors can to some extent decrease the mortality in the most animal models of mild hepatic cell necrosis and acute hepatitis; however, it cannot effectively decrease the mortality of acute or sub-acute hepatic failure caused by massive hepatocyte necrosis. Furthermore, the reason of the poor therapeutic effect is still not known so far by those of the skill in the art. Consequently, it is still difficult now for the soluble TNFα receptors to find their use practically in clinical applications to treat massive hepatocytes necrosis or hepatic failure.
In summary, there is an earnest demand in the art to find the reason for the poor therapeutic effect of TNFαreceptors for treating hepatic cell necrosis, so as to modify the TNFαreceptors to confer it the ability to effectively and rapidly prevent the occurrence of extensive acute necrosis of hepatocytes, and thereby making it a superior medicament for clinically treating and preventing acute and sub-acute hepatic failure.
Contents of the Invention
In the first aspect, the present invention provides a use of long-acting soluble tumor necrosis factor αreceptor in the manufacture of a medicament for the treatment and/or prophylaxis of hepatocyte necrosis or hepatic failure.
In a preferred embodiment, the long-acting soluble tumor necrosis factor αreceptor is a long-acting recombinant human soluble tumor necrosis factor αreceptor.
In a further preferred embodiment, the long-acting soluble tumor necrosis factor α receptor has a half-life of 12-140 hours (preferably, 24-72 hours).
In a further preferred embodiment, the long-acting soluble tumor necrosis factor α receptor is selected from the group consisting of:
a. a fusion protein of human tumor necrosis factor αreceptor type I with human IgG1:Fc fragment (preferably, the carboxyl terminal of the human tumor necrosis factor αreceptor type I being linked to the amino terminal of the IgG1:Fc fragment),
b. a fusion protein of human tumor necrosis factor αreceptor type II with human IgG1:Fc fragment (preferably, the carboxyl terminal of the human tumor necrosis factor α receptor type II being linked to the amino terminal of the IgG1:Fc fragment),
c. a human tumor necrosis factor αreceptor type I protein PEGylated at the amino terminal,
d. a human tumor necrosis factor αreceptor type I protein PEGylated at the carboxyl terminal,
e. a human tumor necrosis factor αreceptor type II protein PEGylated at the amino terminal,
f. a human tumor necrosis factor αreceptor type II protein PEGylated at the carboxyl terminal,
h. a human tumor necrosis factor αreceptor type I protein embedded in a PEG-liposome mixture,
i. a human tumor necrosis factor α receptor type II protein embedded in a PEG-liposome mixture,
j. a fusion protein of human tumor necrosis factor αreceptor type I with human serum albumin, or
k. a fusion protein of human tumor necrosis factor αreceptor type II with human serum albumin.
In a further preferred embodiment, the long-acting soluble tumor necrosis factor α receptor decreases the IL-6 level in hepatocytes by 40-50%;
decreases the MIP-2 level in hepatocytes by 50-60%;
decreases the bcl-xl level in hepatocytes by 30-45%; or
decreases the NF-κB level in hepatocytes by 30-45%.
In a further preferred embodiment, the hepatic failure is acute and/or sub-acute hepatic failure.
In a further preferred embodiment, the hepatocyte necrosis is massive hepatocyte necrosis.
In a further preferred embodiment, the hepatocyte necrosis is acute massive hepatocyte necrosis.
In the second aspect, the present invention provides a pharmaceutical composition comprising:
(i) an effective amount (for example, 0.00001-50wt %; more preferably, 0.0001-20wt %; the most preferably, 0.001-10wt %) of a long-acting soluble tumor necrosis factor αreceptor selected from the group consisting of:
a. a fusion protein of human tumor necrosis factor αreceptor type I with human IgG1:Fc fragment (preferably, the carboxyl terminal of the human tumor necrosis factor αreceptor type I being linked to the amino terminal of the IgG1:Fc fragment),
b. a fusion protein of human tumor necrosis factor αreceptor type II with human IgG1:Fc fragment (preferably, the carboxyl terminal of the human tumor necrosis factor α receptor type II being linked to the amino terminal of the IgG1:Fc fragment),
c. a human tumor necrosis factor αreceptor type I protein PEGylated at the amino terminal,
d. a human tumor necrosis factor αreceptor type I protein PEGylated at the carboxyl terminal,
e. a human tumor necrosis factor αreceptor type II protein PEGylated at the amino terminal,
f. a human tumor necrosis factor αreceptor type II protein PEGylated at the carboxyl terminal,
h. a human tumor necrosis factor αreceptor type I protein embedded in a PEG-liposome mixture,
i. a human tumor necrosis factor α receptor type II protein embedded in a PEG-liposome mixture,
j. a fusion protein of human tumor necrosis factor αreceptor type I with human serum albumin, or
k. a fusion protein of human tumor necrosis factor αreceptor type II with human serum albumin; and
(ii) a pharmaceutically acceptable vehicle.
In a further preferred embodiment, the pharmaceutical composition further comprises an effective amount (for example, 0.00001-50wt %; more preferably, 0.0001-20wt %; the most preferably, 0.001-10wt %) of one or more agents selected from the group consisting of:
(iii) human hepatocyte growth factor (huHGF), reduced glutathione and matrine.
In the third aspect, the present invention provides a method of treating or preventing the hepatocyte necrosis or the hepatic failure, comprising the step of administering to a subject in need of such a treatment an effective amount (for example, 0.00001-50wt %; more preferably, 0.0001-20wt %; the most preferably, 0.001-10wt %) of a long-acting soluble tumor necrosis factor αreceptor.
In a preferred embodiment, the long-acting soluble tumor necrosis factor αreceptor is selected from the group consisting of:
a. a fusion protein of human tumor necrosis factor αreceptor type I with human IgG1:Fc fragment (preferably, the carboxyl terminal of the human tumor necrosis factor αreceptor type 1 being linked to the amino terminal of the IgG1:Fc fragment),
b. a fusion protein of human tumor necrosis factor αreceptor type II with human IgG1:Fc fragment (preferably, the carboxyl terminal of the human tumor necrosis factor α receptor type II being linked to the amino terminal of the IgG1:Fc fragment),
c. a human tumor necrosis factor αreceptor type I protein PEGylated at the amino terminal,
d. a human tumor necrosis factor αreceptor type I protein PEGylated at the carboxyl terminal,
e. a human tumor necrosis factor αreceptor type II protein PEGylated at the amino terminal,
f. a human tumor necrosis factor αreceptor type II protein PEGylated at the carboxyl terminal,
h. a human tumor necrosis factor αreceptor type I protein embedded in a PEG-liposome mixture,
i. a human tumor necrosis factor α receptor type II protein embedded in a PEG-liposome mixture,
j. a fusion protein of human tumor necrosis factor αreceptor type I with human serum albumin, or
k. a fusion protein of human tumor necrosis factor αreceptor type II with human serum albumin;
In a preferred embodiment, the hepatic failure is acute and/or sub-acute hepatic failure.